The Ninth International Meeting on N-Nitroso Compounds: Relevance to Human Cancer will be held in Vienna, Austria, from September 1-5, 1986, for which organizational and scientific planning by IARC staff is well advanced. One of the major goals of this conference is to stimulate multidisciplinary investigations in the field of nitrosamine research and facilitating the integration of laboratory and epidemiological approaches with a major focus on N-nitroso compounds, a versatile and potent class of animal and suspected human carcinogens. Invited review lectures and proffered papers will discuss the following areas: a) fundamental research on molecular and cellular mechanisms of carcinogenesis by nitroso compounds as to why this class of carcinogens produces tumours in 40 animal species and displays remarkable species-and organ-specificity and a wide variety of genetic effects; b) methodological developments to determine the level of nitroso compounds in the external and internal environment of man, using ultra-sensitive detection methods, including those to measure macromolecular adducts in human cells; c) application of these methods for the identification of subjects/populations highly exposed to nitroso compounds, and to correlate such exposures with human cancers at specific sites; d) search for preventive measures by which the body burden of such nitroso carcinogens can be efficiently lowered and/or their adverse biological effects be diminished. Discussions during this meeting will be facilitated through precirculation of all manuscripts to participants. The Proceedings volume of all presented scientific papers will be published in the IARC Scientific Publications series. As with the previous volumes, this will be an authoritative source of recent information on on-going environmental research and applications in biochemical epidemiology and will be disseminated by IARC and Oxford University Press.